It depends on what kind of grass that you have. If you have a Blue grass lawn, Rye or Fescue you should use a lawn reel mower that has 5 to 6 blades. If you have a lawn of Bermuda or Bent you should have a lawn reel mower with 7 to 9 baldes on the reel.

Do I want wheels or a roller in the back of my lawn reel mower?

This is up to you. The small wheels in the back help you mow strait. A roller in the back helps stripe your lawn like profestional would.

How fast should I push my lawn reel mower?

A steady walking pace is good. The reel on the lawn reel mower is designed to go faster if you walk faster. If you notice some grass not being cut slow down it usually will work better.